You see that's the problem when using splines.
As soon as ou get a high number of them,the surface isn't smooth anymore and the shading looks aweful.It's their own nature,the less the better.
It's a best practice to model organic stuff(if not everything) using polygons and/or subdivision surfaces.
A good control over the density of the cage and the subd will let you generate a mesh under 2-3000 triangles.Awaiting for further reshaping.
That and the fact that you won't end up having to optimize it before dropping it into your game.
BlackBird thinks he owns the sky,
But he can't look me in the eye,
-Andy Bell